Just thinking "out loud" here :)
So using the camp($20) and hotel($60)
lodging should run us around $1700.
and if gas around $1300.
That leaves us $3000 for food and fun. so about $55 - $65 per day.
i don't know if that is enough... it's so hard to plan for food and activities because we don't know what we're going to want to do/eat.... and I will say this... We do love good food.
I do plan on getting the National Park Pass for $80 that someone else mentioned on another thread. Seems like an awesome deal.